Magnetic resonance imaging of the temporomandibular joints (TMJ)
Temporomandibular joint (TMJ) MRI in Casablanca
The temporomandibular joints (TMJ) connect the lower jaw to the skull, just in front of each ear. Between the two bones is a small disc of cartilage that slides when the mouth opens. MRI is the exam that makes it possible to see this disc directly, along with its position and movement, as well as the condition of the bones and the joint fluid. Both sides are examined in the same session, first with the mouth closed, then with the mouth open.
Duration, report and equipment
Duration
The exam usually takes 20 to 30 minutes.
Report turnaround
Report within 48 hours. In an emergency, during opening hours, the report is handed over immediately.
Equipment
GE SIGNA Prime 1.5 T
When is this exam needed?
- Pain in front of the ear or in the jaw, especially when chewing.
- Repeated clicking or popping when opening the mouth.
- Jaw locking or limited mouth opening.
- Assessment before orthodontic treatment, a splint or jaw surgery.
- Persistent pain after a blow to the chin or jaw.
- Involvement of the joint in an inflammatory rheumatic disease.
How the exam is done
You lie on your back. Small coils are placed on each side of your face, against the joints, or your head is placed in a head coil. A first series of images is taken with the mouth closed, teeth touching without clenching.
You are then asked to open your mouth, most often with the help of a small block placed between your teeth, and to stay still like this for one or more sequences. Some protocols record several degrees of opening to follow the path of the disc. Keeping your mouth open can be uncomfortable if the joint is painful: say so, the sequences are short and breaks are possible. Apart from this, the exam is painless.
Preparation
- Remove removable dentures and facial piercings.
- Tell us if you have fixed orthodontic braces or dental implants.
- If pain limits how wide you can open your mouth, take your usual painkiller before you come.
- Avoid makeup and hair products on the day of the exam.
Fasting
No fasting is required: you can eat and drink normally before the exam.
Contrast injection
The exam is most often done without a contrast agent. A gadolinium injection through a vein in the arm may be added if inflammation of the joint is being looked for.
Contraindications and precautions
- Implanted device (pacemaker, defibrillator, neurostimulator): the exam depends on the model and its compatibility.
- Cochlear implant, which you must report because it is located very close to the joint.
- Metal fragment in the eye, older vascular clip or implanted pump.
- Insulin pump or glucose sensor (such as FreeStyle Libre): to be removed before the exam. Bring what you need to replace it or put it back afterwards.
- Current or possible pregnancy: please tell us. MRI is performed only if it is necessary, preferably after the first trimester, and without gadolinium unless absolutely necessary.
- Inability to open the mouth or to lie down, so that the protocol can be adapted.
- Tattoos, permanent makeup and claustrophobia.
Documents to bring
- Prescription from the dentist, orthodontist, stomatologist or maxillofacial surgeon
- Previous dental X-rays, panoramic X-ray or cone beam CT
- List of your medications
- Insurance or mutual insurance fund card
Price and insurance coverage
The price of a temporomandibular joint MRI depends on whether one side or both sides are examined, and on a gadolinium injection, which is rarely needed.
The center accepts coverage from insurance companies and the main mutual insurance funds. You submit the coverage request to your insurer or fund yourself. For AtlantaSanad and Sanlam, the center takes care of it.
No prices are shown on this site: Kenza gives you the exact price on WhatsApp, along with the coverage procedure for your situation.
Frequently asked questions
Why do I need to open my mouth during the exam?
The joint disc moves when the jaw opens. Comparing the images with the mouth closed and open shows whether it slides normally, whether it moves back into place during opening, which often causes a click, or whether it stays stuck toward the front.
How is it different from an X-ray or a cone beam CT?
X-rays and cone beam CT show the bones: the shape of the condyle, wear, osteoarthritis. They do not show the disc, which is made of cartilage. MRI shows the disc, the bone and any joint effusion at the same time, without X-rays. These exams complement each other.
Are my dental crowns or implants a problem?
They are generally not dangerous. However, the metal can create blurred areas on the images, sometimes extending to the joints. Tell the radiographer about them, and the radiologist will adjust the settings. Fixed orthodontic braces are the most frequent source of interference.
Why examine both sides if only one hurts?
The two joints work together, and an abnormality on the side that does not hurt is common. Examining them in the same session allows them to be compared and gives your practitioner a complete picture for choosing the treatment.
Temporomandibular joint (TMJ) MRI in Casablanca: how much does it cost?
The price of a temporomandibular joint MRI depends on whether one side or both sides are examined, and on a gadolinium injection, which is rarely needed. The center accepts coverage from insurance companies and the main mutual insurance funds. No prices are shown on this site: Kenza gives you the exact price on WhatsApp, along with the coverage procedure for your situation.